package leecode

func smallestRepunitDivByK(k int) int {
	if k%2 == 0 || k%5 == 0 {
		return -1
	}
	var (
		result int = 1
		num    int
	)
	for {
		num = ((num * 10) + 1) % k
		if num == 0 {
			return result
		}
		result++
	}
}

//1456 1679 443 1969
